Search PubMed⌕ Search

Biomedical subjects

J Kudoh

Publications and source records attributed to J Kudoh.

At least 55 records · Page 3Linked to original sources
PubMed1998

Mouse myocilin (Myoc) gene expression in ocular tissues.

Human myocilin is identical to TIGR (trabecular meshwork inducible glucocorticoid response) which is responsible for the pathogenesis of juvenile-onset primary open angle glaucoma (GLCIA). We have isolated cDNA for mouse myocilin (Myoc) and investigated mouse myocilin gene expression in ocular tissues with in situ RNA hybridization. Hybridization signals were observed in the iris, ciliary body, trabecular meshwork, sclera, and retina in the mouse eye. The marked signals were seen in trabecular meshwork cells and the anterior portion of sclera. These findings suggest that myocilin mutation could affect the capacity of aqueous outflow and cause elevation of the intraocular pressure which is involved in the pathogenesis of glaucoma.

Amino Acid Sequence↗
PubMed1998

Genomic organization of the human myocilin gene (MYOC) responsible for primary open angle glaucoma (GLC1A).

Myocilin is a newly found cytoskeletal protein involved in the morphogenesis of the basal body, a major microtubule organizing center, of the ciliated epithelium. It was recently realized that myocilin is virtually identical to the independently reported protein TIGR (trabecular meshwork-induced glucocorticoid response), which is responsible for the pathogenesis of chromosome 1q-linked primary open angle glaucoma (GLC1A). In this paper, we determined the genomic organization of the myocilin (MYOC/TIGR) gene by analyzing the nucleotide sequence of the BAC clones containing the MYOC/TIGR gene. The MYOC/TIGR gene consists of three exons. Each of the two splice donor and acceptor sites agrees well with the GT/AG rule. Primer sets to amplify each of the three exons are designed. The 5'-flanking region of MYOC gene contains the TGTTCT sequence overlapped with a palindromic sequence TTCTTTTTAAAAAGAA, which appears to be a glucocorticoid responsive element. There is also a unique sequence of dinucleotide repeat [(GT)2AA(GT)4AC(GT)13] which may also serve as a regulatory element. These results should aid in further detection of the MYOC/TIGR gene mutation and in depth understanding of the tissue-specific MYOC gene regulation.

Amino Acid Sequence↗
PubMed1998

Identification and characterization of a novel cyclic nucleotide phosphodiesterase gene (PDE9A) that maps to 21q22.3: alternative splicing of mRNA transcripts, genomic structure and sequence.

Cyclic nucleotide-specific phosphodiesterases (PDEs) play an essential role in signal transduction by regulating the intracellular concentration of second messengers (cAMP and cGMP). We have identified and made an initial characterization of a full-length cDNA encoding a novel human cyclic nucleotide phosphodiesterase, PDE9A. At least four different mRNA transcripts (PDE9A1, A2, A3, A4) are produced as a result of alternative splicing of 5' exons, potentially changing the N-terminal amino acid sequences of the encoded proteins. All these predicted proteins would contain a 3',5'-cyclic nucleotide phosphodiesterase signature motif (Prosite no. PDOC00116). Northern blot analysis revealed several mRNA species of approximately 2.4 kb with varying expression patterns and intensities in most tissues examined, except blood. We have also isolated the mouse homolog of the human PDE9A2 mRNA transcript, pde9A2. The human and mouse isoforms have 93 and 83% sequence identity at the amino acid and nucleotide levels, respectively. PDE9A was mapped to 21q22.3, between TFF1 and D21S360. Comparison of the PDE9A1 cDNA with the genomic sequence from the region revealed that the gene is split into 20 exons that extend over 122 kb. Comparison of the physical map of the region and the genomic sequence further refines the mapping, with D21S113 being derived from intron 15. Several genetic disorders map to 21q22.3, including one form of bipolar affective disorder. Since functional disturbances in intraneuronal signal transmission via second messengers play an important role in the pathophysiology of affective disorders, PDE9A is a strong candidate for such a role by position and function.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1998

A common mutation in Sardinian autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy patients.

Autoimmune polyendocrinopathy-candidiasisectodermal dystrophy (APECED; also called APS-1,) is a rare autosomal recessive disorder that is more frequent in certain isolated populations. It is characterized by two of the three major clinical symptoms that may be present: Addison's disease, and/or hypoparathyroidism and/or chronic mucocutaneous candidiasis. We have recently identified the gene for APECED, which we termed AIRE (for autoimmune regulator). AIRE is expressed in thymus, lymph nodes and fetal liver, and encodes a protein with two putative zinc fingers and other motifs suggestive of a transcriptional regulator. Seven mutations have been described to date, including R257X, the predominant Finnish and northern Italian APECED allele, which has also been observed in other patients of diverse origin on different haplotypes. A 13-bp deletion (1094-1106del) has also been observed in several patients of different geo-ethnic origin. The other described mutations appear to be rare. We present mutational analyses of the AIRE gene in ten Sardinian APECED families and show that there is a mutation, R139X, associated with one predominant haplotype unique to the Sardinian patients (18/20 independent alleles). The carrier frequency of R139X in Sardinia is 1.7%, giving an estimated population frequency of APECED of 1/14,400. Using linkage disequilibrium data, the estimated age of the R139X mutation is between 20 and 25 generations. A previously described 13-bp deletion was also observed on an allele of one patient. The identification of a single common Sardinian APECED mutation will facilitate its genetic diagnosis. Given the carrier frequency of R139X in the Sardinian population, AIRE may be implicated in the pathogenesis of other autoimmune diseases in the Sardinian population, particularly those affecting the endocrine system.

DNA Mutational Analysis↗
PubMed1998

The classic form of granular corneal dystrophy associated with R555W mutation in the BIGH3 gene is rare in Japanese patients.

PURPOSE: To identify the BIGH3 gene mutation in 10 unrelated Japanese individuals with granular corneal dystrophy. METHODS: Genomic DNA was obtained from each patient's leukocytes. Exons 4 and 12 of the BIGH3 gene were amplified by polymerase chain reaction and were directly sequenced. RESULTS: Nine of these patients were found to have the R124H mutation, whereas only one had the R555W mutation. Slit-lamp examination showed that the granular corneal dystrophy associated with each mutation is different. CONCLUSIONS: These results, together with our previous findings, show that the classic form of granular corneal dystrophy associated with the R555W mutation is rare in Japanese patients, whereas granular corneal dystrophy accompanied by amyloid deposits and associated with the R124H mutation, Avellino corneal dystrophy, is more common. Direct examination may be insufficient in the proper diagnosis of corneal dystrophy, and BIGH3 mutation analysis may be required.

Adult↗
PubMed1998

A novel homozygous Ile535Asn mutation in the rod cGMP phosphodiesterase beta-subunit gene in two brothers of a Japanese family with autosomal recessive retinitis pigmentosa.

PURPOSE: Recently, mutations in several genes have been identified as being responsible for the pathogenesis of autosomal recessive retinitis pigmentosa (arRP). These genes include rhodopsin, beta-subunit of rod cGMP phosphodiesterase (PDEB), alpha-subunit of rod cGMP phosphodiesterase (PDEA), and alpha-subunit of rod cGMP-gated channel. We here attempted to identify a novel mutation in the PDEB gene in Japanese arRP patients. METHODS: Using the PCR-SSCP method, sequencing analysis, and restriction endonuclease digestion assay, we analyzed the PDEB gene in 17 Japanese families with non-dominant retinitis pigmentosa. RESULTS: A novel Ile535Asn mutation was identified in two patients in a single family and the mutation cosegregated with RP in this family. Among 90 unrelated healthy individuals, no one was identified as homozygous for this mutation, except for one individual who was found to be heterozygous. CONCLUSIONS: Isoleucine at codon 535 in the PDEB gene is conserved among various mammals. Missense mutations of the PDEB gene causing arRP have been reported in a limited region (codon 527-codon 699) in which codon 535 is located. Thus, the Ile535Asn mutation is an additional missense mutation which is responsible for the pathogenesis of arRP.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1998

Spectrum of pathogenic mitochondrial DNA mutations and clinical features in Japanese families with Leber's hereditary optic neuropathy.

PURPOSE: To investigate the incidence and clinical significance of primary or proposed secondary mitochondrial DNA (mtDNA) mutations in Japanese patients with Leber's hereditary optic neuropathy (LHON). METHODS: Blood samples from the 80 unrelated Japanese patients with bilateral optic atrophy were screened for primary LHON mutations. Patients found to have a primary LHON mutation were then tested for 9 proposed secondary LHON mutations. We investigated the association between these mutations and clinical characteristics. RESULTS: Primary mtDNA mutations were identified in 68 patients: at np 3460 in 3 (4%) of 68 patients, at np 11,778 in 59 patients (87%), and at np 14,484 in 6 patients (9%). We identified 5 secondary mtDNA mutations (at np 3394, 4216, 7444, 9438 or 13,708) in 10 (15%) of 68 LHON patients and 3 mutations (at np 3394, 4216 or 3708) in 6 (7%) of 90 healthy Japanese individuals. No patient was positive for more than one secondary mutation. The frequency of secondary mutations was similar in the 68 LHON patients and 90 controls. The clinical features of the Japanese patients with any of the 3 primary LHON mutations were similar to those of Caucasian patients, despite different mtDNA backgrounds in these populations. The percentage of patients with familial LHON harboring the 3460 or 14,484 mutations was lower in the Japanese population. CONCLUSIONS: Japanese patients with LHON exhibited a very high incidence (87%) of the 11,778 primary mutation. Most of the proposed secondary LHON mutations were rare in the Japanese population and they, except the 7444 mutation, may not influence the clinical features of LHON.

Adolescent↗
PubMed1998

Severe form of juvenile corneal stromal dystrophy with homozygous R124H mutation in the keratoepithelin gene in five Japanese patients.

AIM: To confirm the mutation of the keratoepithelin gene in patients with a severe form of superficial juvenile granular corneal dystrophy (GCD). METHODS: Five Japanese probands in whom GCD was diagnosed after histopathological examination and who developed severe manifestations of GCD in their first decade of life were investigated. Other affected family members of two probands were also examined. All probands were the offspring of consanguineous parents. DNA was extracted from their peripheral blood leucocytes and mutational analysis of the gene was performed by the polymerase chain reaction and direct sequencing. RESULTS: Four of the five probands underwent their first keratectomy or keratoplasty in their teens and subsequently underwent a second or third keratoplasty. Each proband had a homozygous G-->A transition at codon 124, replacing Arg-->His, of the keratoepithelin gene. Their moderately affected family members were heterozygous for the mutation. CONCLUSIONS: This finding suggests that the severity of the corneal phenotype depends on the dose effect of the mutant gene.

Adult↗
PubMed1998

Common mutations in autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy patients of different origins.

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED; OMIM *240300, also called APS 1,) is a rare autosomal recessive disorder that is more frequent in certain isolated populations. It is generally characterized by two of the three major clinical symptoms that may be present, Addison's disease and/or hypoparathyroidism and/or chronic mucocutaneous candidiasis. Patients may also have a number of other clinical symptoms including chronic gastritis, gonadal failure, and rarely, autoimmune thyroid disease and insulin-dependent diabetes mellitus. We and others have recently identified the gene for APECED, which we termed AIRE (for autoimmune regulator). AIRE is expressed in thymus, lymph nodes, and fetal liver and encodes a protein containing motifs suggestive of a transcriptional regulator, including two zinc finger motifs (PHD finger), a proline-rich region, and three LXXLL motifs. Six mutations, in cluding R257X, the predominant Finnish APECED allele, have been defined. R257X was also observed in non-Finnish APECED patients occurring on different chromosomal haplotypes suggesting different mutational origins. Here we present mutation analyses in an extended series of patients, mainly of Northern Italian origin. We have detected 12 polymorphisms, including one amino acid substitution, and two additional mutations, R203X and X546C, in addition to the previously described mutations, R257X, 1096-1097insCCTG, and a 13-bp deletion (1094-1106del). R257X was also the common mutation in the Northern Italian patients (10 of 18 alleles), and 1094-1106del accounted for 5 of 18 Northern Italian alleles. Both R257X and 1094-1106del were both observed in patients of four different geo-ethnic origins, and both were associated with multiple different haplotypes using closely flanking polymorphic markers showing likely multiple mutation events (six and four, respectively). The identification of common AIRE mutations in different APECED patient groups will facilitate its genetic diagnosis. In addition, the polymorphisms presented provide the tools for investigation of the involvement of AIRE in other autoimmune diseases, particularly those affecting the endocrine system.

Female↗
PubMed1997

Cloning of the cDNA for a new member of the immunoglobulin superfamily (ISLR) containing leucine-rich repeat (LRR).

We isolated cDNAs for a novel protein with a calculated molecular mass of 46 kDa, containing a leucine-rich repeat (LRR) with conserved flanking sequences and a C2-type immunoglobulin (Ig)-like domain. This novel protein was considered to be a new member of the Ig superfamily and was named ISLR (immunoglobulin superfamily containing LRR). These domains are known to be important for protein-protein interaction or cell adhesion, and therefore it is possible that the novel protein ISLR may also interact with other proteins or cells. Northern blot analysis showed the presence of a 2.4-kb transcript in various human tissues including retina, heart, skeletal muscle, prostate, ovary, small intestine, thyroid, adrenal cortex, testis, stomach, and spinal cord as well as fetal lung and fetal kidney. The ISLR gene was mapped on human chromosome 15q23-q24 by fluorescence in situ hybridization.

Amino Acid Sequence↗
PubMed1997

Genomic organization and complete nucleotide sequence of the human PWP2 gene on chromosome 21.

The human PWP2 gene is the human homologue of the yeast periodic tryptophan protein 2 (PWP2) gene and is a member of the gene family that contains tryptophan-aspartate (WD) repeats. Genomic sequencing revealed that the human PWP2 gene consists of 21 exons spanning approximately 24 kb and locates just between the two genes EHOC-1 and KNP-I and distal to a NotI site of LJ104 (D21S1460) on chromosome 21q22.3. Analysis of the 5'-flanking DNA sequence revealed that the upstream region of the PWP2 gene is associated with a CpG island containing the NotI site of LJ104. Since PWP2 is considered to be a candidate for genetic disorders mapped in the 21q22.3 region, the information including nucleotide sequence and genomic organization of the PWP2 gene should be invaluable for the mutation analysis of the corresponding genetic disorders.

Base Sequence↗
PubMed1997

Genomic organization and complete nucleotide sequence of the TMEM1 gene on human chromosome 21q22.3.

TMEM1 (EHOC-1) gene encodes a putative transmembrane protein and is located on human chromosome band 21q22.3. Analysis of a 122,638-bp genomic sequence revealed that TMEM1 gene consists of 23 exons spanning approximately 94 kb and is transcribed in the direction of centromere to telomere. The 5' region of the TMEM1 gene was associated with a CpG island and the 3' end of the TMEM1 gene was mapped just proximal to the 5' end of the neighboring gene PWP2. We determined that the TMEM1 gene encodes a protein of 1,259 amino acids, which is 69-amino acids longer than the previously reported sequence. Since TMEM1 gene is considered to be a candidate for genetic disorders mapped in the 21q22.3 region, the information including complete nucleotide sequence and genomic organization of the TMEM1 gene should be invaluable for the mutation analysis of the corresponding genetic disorders.

Amino Acid Sequence↗
PubMed1997

Human BAC library: construction and rapid screening.

We have constructed a human genomic bacterial artificial chromosome (BAC) library using high molecular weight DNA from a pre-pro-B cell line, FLEB14-14, with a normal male diploid karyotype. This BAC library consists of 96,000 clones with an average DNA insert size of 110 kb, covering the human genome approximately 3 times. The library can be screened by three different methods. (1) Probe hybridization to 31 high-density replica (HDR) filters: each filter contains 3072 BAC clones which were gridded in a 6 x 6 pattern. (2) Probe hybridization to two Southern blot filters to which 31 HindIII digests of the pooled 3072 BAC clones were loaded. This identifies a particular HDR filter for which further probe hybridization is performed to identify a particular clone(s). (3) Two-step polymerase chain reaction (PCR). First, PCR is applied to DNA samples prepared from ten superpools of 9600 BAC clones each to identify a particular superpool and the second PCR is applied to 40 unique DNA samples prepared from the four-dimensionally assigned BAC clones of the particular superpool. We present typical examples of the library screening using these three methods. The two-step PCR screening is particularly powerful since it allows us to isolate a desired BAC clone(s) within a day or so. The theoretical consideration of the advantage of this method is presented. Furthermore, we have adapted Vectorette method to our BAC library for the isolation of terminal sequences of the BAC DNA insert to facilitate contig formation by BAC walking.

B-Lymphocytes↗
PubMed1997

A novel myosin-like protein (myocilin) expressed in the connecting cilium of the photoreceptor: molecular cloning, tissue expression, and chromosomal mapping.

We have isolated a human cDNA clone encoding a novel acidic protein of MW 55,000 that we designated "myocilin" since it has homology to myosin and is localized preferentially in the ciliary rootlet and basal body of the connecting cilium of photoreceptor cells. The deduced amino acid sequence of human myocilin showed significant homologies with nonmuscle myosin of Dictyostelium discoideum in the N-terminal region and also with olfactomedin of bullfrog in the C-terminal region. Myocilin contained a leucine zipper-like motif similar to that seen in kinectin and other cytoskeletal proteins. These findings suggest that myocilin is a novel cytoskeletal protein involved in the morphogenesis of ciliated neuroepithelium such as photoreceptor cells. The myocilin gene (MYOC) was mapped to human chromosome 1q23-q24 by fluorescence in situ hybridization.

Amino Acid Sequence↗
PubMed1997

Human retina-specific amine oxidase (RAO): cDNA cloning, tissue expression, and chromosomal mapping.

In search of candidate genes for hereditary retinal disease, we have employed a subtractive and differential cDNA cloning strategy and isolated a novel retina-specific cDNA. Nucleotide sequence analysis revealed an open reading frame of 2187 bp, which encodes a 729-amino-acid protein with a calculated molecular mass of 80,644 Da. The putative protein contained a conserved domain of copper amine oxidase, which is found in various species from bacteria to mammals. It showed the highest homology to bovine serum amine oxidase, which is believed to control the level of serum biogenic amines. Northern blot analysis of human adult and fetal tissues revealed that the protein is expressed abundantly and specifically in retina as a 2.7-kb transcript. Thus, we considered this protein a human retina-specific amine oxidase (RAO). The RAO gene (AOC2) was mapped by fluorescence in situ hybridization to human chromosome 17q21. We propose that AOC2 may be a candidate gene for hereditary ocular diseases.

Adult↗
PubMed1997

Localization of 16 exons to a 450-kb region involved in the autoimmune polyglandular disease type I (APECED) on human chromosome 21q22.3.

As a step toward identifying the pathogenic genes for autoimmune polyglandular disease type I (APECED) and other disorders mapped to the PFKL locus on chromosome 21q22.3, we have constructed a cosmid/BAC (bacterial artificial chromosome) contig of 450 kb covering markers D21S1460-D21S25-PFKL-D21S154 and performed exon trapping. We isolated 22 distinct exons including 6 exons derived from two known genes (PFKL and EHOC-1). Among 16 novel exons, 2 exons matched with human expressed sequence tags (EST) and 7 exons showed homology at predicted amino acid sequence level with proteins from other species. These 16 exons were mapped back to the cosmid contigs, 12 of which were confirmed for their expression by polymerase chain reaction (PCR) screening of human cDNA libraries of various tissues. These exon sequences and a transcript map will aid for isolation of corresponding genes which will be identified as candidate genes involved in the pathogenesis of disorders mapped to the 21q22.3 region.

Amino Acid Sequence↗